And according to Ahmed and Haunss, it's not just the little guys
who are making the blacklist. Hedge fund giants Fortress
Investment Group, Highland Capital Management, and Cerberus
Capital were all blocked from investing in RBS Holding Company's
$155 million Quadriga Art loan last year.

Companies tend to blacklist investors who are known to be tough
on debt restructuring, affiliated with a competitor, or, simply,
on the company's bad side, they reported.

This phenomenon, which seems to have took off back in the 1990s,
is surprisingly widespread. Some 77% of loans made last
quarter allowed borrowers to block specific investors, while last
year, the number was only 51%, the reporter said.

Blacklisting can be a problem because it cuts down on potential
buyers, meaning the loans can become difficult to trade.